Nonwoven applique material

ABSTRACT

A nonwoven applique material for use in disposable garments worn in contact with the skin comprising a scrim with an applique adhesively bonded to the scrim. The applique is impregnated with predetermined amounts of certain acrylic adhesives and ammonium sulfamate to provide a soft material having self-extinguishing and abrasion resistance properties.

United States Patent 1191 Goldbeck 1451 Oct. 2, 1973 [54] NONWOVENAPPLIQUE MATERIAL 2,902,037 9/1959 Harwood et a1. 128/290 3,025,1993/1962 Harwood 161/57 [751 Lemy Gmdbeck, Neenah, 3,072,511 1/1963Harwood 161/57 73 Assigneez Ki c Corporation, 3,307,992 3/1967 Condon eta1. 156/181 Neenah wis 2,902,395 9/1959 Hlrschy et al 161/57 2,723,21211/1955 Aarons et a1. 117/137 [22] Filed: Jan. 25, 1971 2,991,143 7/1961Rosenlind 117/137 2,537,323 1/1951 Wurzburger 161/57 [21] Appl. No.:109,528

Related US. Application Data Continuation-impart of Ser. No. 800,582,Feb. 19, 1964, abandoned.

US. Cl. 161/57, 117/137, 161/146, 161/156, 161/157 Int. Cl. 1332b 5/12Field 01 Search 161/57, 79-82, 161/89, 92, 97,113-115, 151; 117/136,137;

References Cited UNITED STATES PATENTS 8/1959 Harwood 128/290 PrimaryExaminer-George F. Lesmes Assistant Examiner-James .1. Bell Att0rneyC.Frederick Leydig et al.

[57] ABSTRACT A nonwoven applique material for use in disposablegarmentsworn in contact with the skin comprising a scrim with anapplique adhesively bonded to the scrim. The applique is impregnatedwith predetermined amounts of certain acrylic adhesives and ammoniumsulfamate to provide a soft material having selfextinguishing andabrasion resistanceproperties.

7 Claims, 2 Drawing Figures PATENTED UCI 21973 Q 1. z ma J 4 Z 'NONWOVENAPPLIQUE MATERIAL This application is a continuation-in-part of mycopending application Ser. No. 800,582, filed Feb. 19, 1969, nowabandoned.

DESCRIPTION OF THE INVENTION The present invention relates generally tononwoven materials and, more particularly, to nonwoven appliquematerials characterized by their improved softness, self-extinguishingand abrasion resistance properties.

Nonwoven materials are coming into widespreaduse as disposablegarmentsbecauseof their relatively low cost and simplicity of manufacture ascompared with .woven materials. One type of nonwoven material that maybe advantageously employed is a scrim, i.e. a crossed thread fabrichaving an open mesh construction. The scrim comprises a set of spacedwarp threads which extend in themachine direction, and a set of spacedfill threads which extend across the warp threads in the transversedirection. The two sets of threads are disposed in a face-to-facerelation to each other, and are adhesively bonded together where thethreads of one set cross the threads of the other set.

The scrim may be combined with one ormore plies of cellulosic waddingbonded to the scrim to form a nonwoven-reinforced material. Thesematerials can be fashioned into various types of outer wear, e.g., adress or gown. However, a material of this type is not generallyemployed for disposable clothing worn in direction contact with theskin, i.e. such as panties and the like, because of insufficientsoftness, hand and feel.

It has been heretofore proposed to deposit a light applique on a scrimmaterial and adhesively bond the applique to the scrim by utilizing theadhesive located on the scrim threads. Attempts to utilize a material ofthis type for use in disposable panties and the like have not beenentirely successful. When such materials are. exposed to the rubbingandabrading actions that take place in the normal usage of-disposablepanties or other garments worn in contact with the skin, some of theapplique fibers become separated and cause a lint problem. All previousattempts to increase the resistance to abrasion have significantlydecreased the softness, hand and feelof the material.

Similarly, the usage of nonwoven applique materials hasbeen limited bytheir inflammability. Providing fire retardancy for the materials hasconcomittantly re- .sulted in significantly diminishing the desirableaesthetic properties.

It is accordingly an object of the present invention to provide animproved nonwoven applique material that may be advantageously employedin disposable garments worn in direct contact with the skin.

Another object of the invention is to provide an improved nonwovenapplique material which is characterized by improved resistance toabrasion. A related and more specific object is to provide a nonwovenapplique material of the hereinbefore described type wherein theapplique fibers are sufficiently bonded to the nonwoven material so thatremoval by the rubbing or abrading that would occur under normalconditions of usage is minimized yet the softness, hand and feel are notdetrimentally affected.

A further object of the invention is to provide an improved nonwovenapplique material that is treated to provide self-extinguishingcharacteristics with superior aesthetic characteristics. A related andmore specific object is to provide such a material with selfextinguishing characteristics that. cannot be readily leached out.

Yet another object of the present invention is to provide such animproved nonwoven applique material which can be readily dyed withoutaffecting the other desirable properties of the material.

Other objects and advantages of the invention will be apparent from thefollowing detailed description taken in conjunction with theaccompanying drawings in which:

FIG. 1 is a perspective view of the nonwoven applique material of thepresent invention witha portion of the applique cut away to show thenonwoven material; and

FIG. 2 is a schematic view illustrating an exemplary method for formingthe nonwoven applique material of the present invention.

While theinvention is susceptible of various modifications andalternative forms, certain specific embodiments thereof have been shownby way of example in the drawingswhich will be described in detailherein.

It should be understood, however, that it is not intended to limit theinvention to the particular forms disclosed, but, on the contrary, theintention is to cover all modifications, equivalents and alternativesfalling within the spirit and scope of the invention.

. Turning now to the drawings, FIG. 1 illustrates an exemplaryembodiment of the nonwoven applique material of the present invention.Thus a scrim, generally indicated at 10, includes a set of spaced warpthreads 12, which extend in the longitudinal or machine direction,

and a set of fill threads 14, which extend across the warp threads inthe transverse direction. Since the scrim is nonwoven, the fill threads14 area on the same side of the warp threads 12, with the two sets ofthreads disposed in a face-to-face relation to each other and adhesivelybonded together, as shown at 16, where the threads of one set cross thethreads of the other set. In the illustrativeembodiment, the softness ofthe material has been maximized by only applying adhesive to the warpthreads 12. It should be appreciated, however, that adhesive couldalsobe applied to the fill threads 14, if desired. I

The relative openness of the scrim l0 canbe varied within wide limits.However, as the number of threads in the scrim increases, the stiffnessalso increases and thus the aesthetic properties become less desirable.On the other hand, as the number of threads used become fewer in number,it is more difficullt to effectively bond the applique to the scrim andthe resistance to abrasion accordingly diminishes. It has been generallyfound to be suitable to employ from about 5 to about 12 threads per inchin each direction.

The denier of the threads may vary from about 10 to 100. As the denieris increased, the stiffness is increased. Employing lower deniers, onthe other hand, reduces the strength of the material. The threadsthemselves may be formed from a variety of synthetic materials withnylon or rayon fibers being preferred. Glass and polyester fibers mayalso be utilized. Similarly, the individual threads can be made ofeither monofilament or multifilament yarn.

An applique 18 is bonded to the scrim 10. The amount of the applique canbe varied from about 10 to perhaps about 60 grams per square yard ofscrim. The particular amount that is employed will depend upon theproperties desired and the particular material employed. Cotton andrayon are preferred because of their superior absorbency characteristicsbut nylon or polyesters may also be used. The lower amounts of appliqueresult in a decrease in opacity, absorbency and softness while thehigher amounts provide an increase in cost without resulting in anysignificantly increased properties.

In accordance with the present invention, the nonwo ven appliquematerial is treated to provide a resulting material that combinessemi-permanent selfextinguishing characteristics with superior softnessand abrasion resistance properties. To this end, the material is madeself-extinguishing by impregnating with from about 10 to about 20 ofammonium sulfamate, based upon the weight of the untreated nonwovenapplique material. Additions below about 10 do not result in anysignificant decrease in the inflammability of the applique materialwhereas amounts above about 20 are not needed to provide the desiredself-extinguishing and improved softness characteristics. Mono ordiammonium phosphate may be subsituted for up to about ilk of theammonium sulfamate.

In conjunction with the addition of the ammonium sulfamate, the nonwovenapplique material is also impregnated with acrylic adhesives to improvethe resistance to abrasion without unduly sacrificing the aestheticproperties and, at the same time, making the selfextinguishingcharacteristics semi-permanent. Thus, the applique is impregnated withan acrylic adhesive having a T, of C. or below (i.e.-the temperature atwhich the torsional modulus of a film of the material is 300 kgJcm).Acrylic adhesives of this type exhibit a tolerance for the ammoniumsulfamate which results in increased permanence, i.e.-minimizes leachingof the ammonium sulfamate which is normally water soluble. The amount ofthe acrylic adhesive should be maintained between from about 5 to about12 based upon the untreated weight of the nonwoven applique material.Below about 5 the abrasion resitance is not significantly increased bythe employment of the adhesive whereas amounts above about 12 result ina substantial decrease in absorbency, etc. Specific examples of acrylicadhesives that may be employed include Rhoplex I-IA-8, manufactured byRohm & Haas Company, Philadelphia, Pennsylvania; Hy car 1562, I-Iycar1572, I-Iycar 2671 and I-Iycar 2679, manufactured by B.F. Goodrich,Akron, Ohio; and Resyn 2813 and Resyn 2833, manufactured by NationalStarch and Chemical Company, New York, New York. It is preferred toemploy Rhoplex I-IA8" which is a nonionic, self cross-linking acrylicemulsion (about 46 solids), having a specific gravity at 25 C. of 1.05and a viscosity (Brookfield viscometer) at 25 C. of 550 cps.

The nonwoven applique material may be readily dyed by any of the dyesthat are conventionally used. For example, Monastral blue," manufacturedby [3.1. DuPont de Nemours & Co., Wilmington, Delaware, can be employed.The amount of dye that will be used is dependent upon the particular dyeand will vary widely, i.e.from about 0.2 to about 10 or more by weight,based on the untreated weight of the nonwoven applique material. Inaddition, other conventionally used additives may be employed. Forexample, a perfume or scent could be included.

As a specific example, the nonwoven applique material of the presentinvention can comprise the followscrim l2 warp threads/inch, 30 denierregular tenacity nylon yarn; 5 fill threads/inch, 7O denier, hightenacity nylon yarn applique cotton 20gms./square yard of scrimimpregnants ammonium sulfamate: about 14 by weight, based on the weightof the untreated scrim and applique; Rhoplex PIA-8 acrylic ahdesive,having a T, ofl4 C.: about 6% by weight.

FIG. 2 illustrates one method for forming the nonwoven applique materialhereinbefore described. There is thus shown a scrim 20, which may bemade by any of several different known methods and apparatus, oneexample of which is described in U.S. Pat. No. 2,841,202 to H.W.Hirschy. In forming the scrim, adhesive has generally been applied tothe warp threads to provide bonding between the warp and fill threads attheir crossover points. Various adhesives may be employed. Plastisolswhich include vinyl chloride polymers, and copolymers of vinyl chlorideswith other vinyl resins, plasticized by organic phthalates, sebacates,or adipates are particularly suitable. Other adhesives that may beemployed include polyvinyl acetate, acrylic resins such as the alkylacrylates, and butadiene resins such as butadiene-styrene and butadieneacrylonitriles.

The scrim 20 is then generally passed through an oven 22 maintained at atemperature in the range of from about 200 F. to 350 F., depending uponthe particular adhesive employed and as is well known.

To form the applique fibers 24 are deposited on the scrim 20 byutilizing a conventional air former, schematically shown at 26. A vacuumbox 28 can be used to aid in depositing the fibers onto the scrim 20. Itshould be appreciated that the applique could also be formed bydepositing a carded web, by using a Rando Weber, or by any other knownmeans.

To reactivate the adhesive on the scrim threads for binding the appliquethereto, the scrim 20 may be passed through a series of pre-heat rolls30 maintained within the temperature range hereinbefore set forth inconnection with the oven. The applique is then calender bonded to thescrim by rolls 32. I

The thus-formed material is then treated in accordance with the presentinvention to improve the adhesive of the applique to the scrim and toprovide selfestinguishing characteristics. In the preferred embodiment,both objectives are carried out together. To this end and as isillustrated, the nonwoven applique material 34 is passed over a turningroll 36 and into a bath 38. The bath is provided with the desiredamounts of ammonium sulfamate and the acrylic binder. The bath mayinclude a conventional defoamer to facilitate processing, if desired.Similarly, the bath may include a dye.

The simultaneous impregnation minimizes the leaching or bleeding of theammonium sulfamate. However, since the presence of ammonium sulfamatewill create an acid pH, it should be appreciated that the acrylicadhesive employed should also be stable at an acid pH. This can beavoided by separately treating the nonwoven applique material with theacrylic adhesive and the ammonium sulfamate. Becasue separate treatmentdetracts from the permanence of the ammonium sulfamate, it is preferredto employ an adhesive that not only has a T of less than 0 C. but alsois stable in the acid pH range.

The material 32 then passes under roll 40, and between squeeze rolls 42.in the bath, the material will generally pick up about four times itsweight of liquid and the squeeze rolls remove the excess. As isconventionally known, the squeeze rolls 42 should be lubricated with thetreating solution, as shown, to prevent disruption or degradation of thematerial. The thusformed scrim applique material can then be wound byany conventional means.

Thus, as has been seen, the present invention provides a nonwovenapplique material that may be advantageously employed for disposablegarments worn in contact with the skin. The ammonium sulfamate not onlyprovides self-extinguishing characteristics but also increases thesoftness, hand and feel. The specific acrylic adhesives employed provideincreased abrasion resistance without significantly affecting theaesthetic properties. In addition, the acrylic adhesives exhibit atolerance for the ammonium sulfamate that tends to minimize leaching inusage of the otherwise watersoluble sulfamate.

I claim as my invention:

1. A nonwoven applique material comprising a scrim and an applique offrom about to about 60 grams per square yard of said scrim, saidapplique being bonded to said scrim and impregnated with from about 10to about of ammonium sulfamate and from about 5 to about l2of an acrylicadhesive having a T, of 0 C. or below, the amounts of the impregnantsbeing based upon the untreated weight of the scrim and applique.

2. The nonwoven applique material of claim 1 wherein the applique iscomposed of a member selected from the group consisting of cotton,rayon, polyesters and nylon.

3. The nonwoven applique material of claim 1 wherein the scrim iscomposed of a material selected from the group consisting of nylon,rayon, glass and polyesters.

4. The nonwoven applique maerial of claim 1 wherein the scrim has 12warp threads per inch and 5 fill threads per inch of a nylonmultifilament yarn.

5. The nonwoven applique material of claim 1 wherein the applique iscotton and is present in an amount of about 20 grams per square yard ofsaid scrim.

6. The nonwoven applique material of claim 1 wherein the ammoniumsulfamate is present in an amount of about 14% and the acrylic adhesivehas a T, of about 14 C. and is present in an amount of about 6%.

7. The nonwoven applique material of claim 1 wherein said applique isimpregnated with a minor amount of a dye.

2. The nonwoven applique material of claim 1 wherein the applique iscomposed of a member selected from the group consisting of cotton,rayon, polyesters and nylon.
 3. The nonwoven applique material of claim1 wherein the scrim is composed of a material selected from the groupconsisting of nylon, rayon, glass and polyesters.
 4. The nonwovenapplique maerial of claim 1 wherein the scrim has 12 warp threads perinch and 5 fill threads per inch of a nylon multifilament yarn.
 5. Thenonwoven applique material of claim 1 wherein the applique is cotton andis present in an amount of about 20 grams per square yard of said scrim.6. The nonwoven applique material of claim 1 wherein the ammoniumsulfamate is present in an amount of about 14% and the acrylic adhesivehas a Ti of about -14* C. and is present in an amount of about 6%. 7.The nonwoven applique material of claim 1 wherein said applique isimpregnated with a minor amount of a dye.